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frontiers of Structural and Civil Engineering 2015年第2期9卷 107-113页

作者： Xi f. XU School of Civil Engineering Beo'ing Jiaotong University Beijing 100044 China

The Green-function-based multiscale stochastic finite element method (MSfEM) has been formulated based on the stochastic variational principle. In this study a fast computing procedure based on the MSfEM is developed to solve random field geotechnical problems with a typical coefficient of variance less than 1. A unique fast computing advantage of the procedure enables computation performed only on those locations of interest, therefore saving a lot of computation. The numerical example on soil settlement shows that the procedure achieves significant computing efficiency compared with Monte Carlo method.

关键词： multiscale finite element settlement perturbation random field geotechnical

Applied statistical functions and multivariate analysis of geochemical compositional data to evaluate mineralization in Glojeh polymetallic deposit,NW Iran

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frontiers of Earth Science 2019年第1期13卷 229-246页

作者： f DARABI-GOLESTAN A HEZARKHANI Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehranIran

Various genesis of epithermal veins as well as host rock cause complication in the modeling process. Thus LINEST and controlling function were applied to improve the accuracy and the quality of the *** LINEST is a model which is based on multiple linear regression and refers to a branch of applied *** method concerns directly to the application oft-test (TINV and TDIST to analyses of variables in the model)and f- test (fDIST,f-statistic to compare different models) *** elimination technique is applied to reduce the number of variables in the model through all the borehole *** 18 steps,an optimized reduced model (ORM)was constructed and ranked in order of importance as Pb >Ag >P >Hg>Mn>Nb >U>Sr>Sn>As > Cu,with the lowest confidence level (CL)of 92% for *** to the epigenetic vein genesis of Glojeh polymetallic deposit,determination of spatial pattems and elemental associations accompanied by anomaly separation were conducted by K-means cluster and robust factor analysis method based on centered log-ratio (clr)transformed ***,12 samples (cluster 2)with the maximum distance from centroid,indicates the intensity of vein polymetallic mineralization in the *** addition, an ORM for vein population was extracted for Sb >A1 > As >Mg >Pb >Cu >Ag elements with the R2 up to 0.99. On the other hand,after 23 steps of optimization process at the host rock population,an ORM Was conducted by Ag >Te >Hg >Pb >Mg >A1 >Sb >As represented in descending order *** revealed that Te and Hg can be considered as pathfinder elements for Au at the host *** on the ORMs at each population Ag,Pb,and As were often associated with Au *** concentration ratio of (tSb × tA1)vein/(tSb × tA1)baekground as an enrichment index can intensify the mineralization ***,Glojeh deposit was evaluated to be classified as a vein-style Au (Ag,Pb,As)-polymetallic mineralization.

关键词： LINEST and controlling function optimized reduced model log-ratio (clr)transformation K-means cluster robust factor analysis pathfinder elements veinstyle Glojeh polymetallic mineralization

fortification Challenges and Needs

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Biomedical and Environmental Sciences 2001年第1期14卷 98-103页

作者： RODOLfO f. fLORENTINO President Philippine Association of Nutrition Philippines

Experience in many parts of the developing world has shown that food fortification offers a cost_effective and sustainable solution to the problem of micronutrient malnutrition. Building on the advances in science and technology and backed by studies on the economic benefits of fortification programs, governments and industry are beginning to respond positively to the call of nutrition advocates to adopt fortification as a long_term strategy. On the other hand, formidable challenges still remain in many countries in Asia, constraining the widespread adoption of this strategy. The science and technology community needs to provide adequate scientific and technological information as basis for planning and decision making. The government faces the challenge of providing the enabling environment for all stakeholders to cooperate in the fortification effort. Industry faces the challenge of adapting its production system to the requirements of fortification in order that they can contribute to social objectives while pursuing their economic objectives. The international and bilateral aid agencies need to seek tried and innovative ways to support the multiple players of food fortification, as these players in turn face the challenges that confront them.

关键词： science and technology production system economic benefits decision making in order

The lattice of idempotent distributive semiring varieties

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Science China Mathematics 1999年第8期42卷 785-804页

作者： f.Pastijn 郭聿琦 Department of Mathematics Statistics and Computer Science Marquette University

A solution is given for the word problem for free idempotent distributive semirings. Using this solution the lattice L(ID) of subvarieties of the variety ID of idempotent distributive semirings is determined. It turns out that L(ID) is isomorphic to the direct product of a four-element lattice and a lattice which is itself a subdirect product of four copies of the lattice L (B) of all band varieties. Therefore L(ID) is countably infinite and distributive. Every subvariety of ID is finitely based.

关键词： idempotent semiring band distributive semiring variety.

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Communications in Theoretical Physics 2011年第10期56卷 745-750页

作者： I.f.Barna KfKI Atomic Energy Research Institute of the Hungarian Academy of Sciences Thermohydraulics Department(KFKI-AEKI)H-1525 BudapestP.O.Box 49Hungary

In this article we will present pure three dimensional analytic solutions for the Navier-Stokes and the continuity equations in Cartesian coordinates. The key idea is the three-dimensional generalization of the well-known self-similar Ansatz of Barenblatt. A geometrical interpretation of the Ansatz is given also. The results are the Kummer functions or strongly related. Our final formula is compared with other results obtained from group theoretical approaches.

关键词： Navier-Stokes equation self-similar solution

An unexpected cellular fountain of youth:platelets provide factors rejuvenating brain functions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 16-18页

作者： Harald f.Langer Department of Cardiology AngiologyHaemostaseology and Medical Intensive CareUniversity Medical Centre MannheimMedical Faculty MannheimHeidelberg UniversityMannheimGermany German Centre for Cardiovascular Research(DZHK) Partner Site Heidelberg/MannheimMannheimGermany European Center for Angioscience Medical Faculty MannheimHeidelberg UniversityMannheimGermany Cardiovascular systems biology Medical Clinic IUniversity Heart Center LübeckLübeckGermany

In a recent manuscript published in Nature,Schroer et *** that platelets and in particular platelet derived Pf-4(CXCL4)are a novel factor,which can rejuvenate the mammalian neuronal system.1 These findings have the potential to trigger an entire new field of research opening new platelet-derived candidate effector molecules for supporting regeneration.

关键词： supporting platelets finding

CRACK GROWTH BEHAVIOR AND fRACTURE fEATURE Of GH2132 UNDER CREEP-fATIGUE CONDITIONS

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Acta Metallurgica Sinica(English Letters) 1997年第6期10卷 495-500页

作者： Geng, M.f. Luoyang Ship Material Research Inst Luoyang China

The superalloy GH2132 is equivalent to A286. The tests were carried out at 550°C under various cyclic frequencies (hold time) and load levels, and the fracture surfaces were examined by using a scanning electron microscope. It was shown that the fracture mode of creep-fatigue and the effect of cyclic loading on crack growth change with the growth of crack and the increase of net-section stress, and both are reversed when the net-section stress is up to the yield stress of material. When σn0.2, cracking is predominantly cyclic-dependent transgranular and cyclic loading accelerates creep crack growth, whereas when σn>σ0.2, the case is reversed.

关键词： Chromium alloys Crack propagation Creep fracture Nickel alloys Rotating disks Superalloys

Optimal Hybrid Deep Learning Enabled Attack Detection and Classificationin IoT Environment

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Computers, Materials & Continua 2023年第4期75卷 99-115页

作者： fahad f.Alruwaili College of Computing and Information Technology Shaqra UniversitySharqaSaudi Arabia

The Internet of Things (IoT) paradigm enables end users to accessnetworking services amongst diverse kinds of electronic devices. IoT securitymechanism is a technology that concentrates on safeguarding the devicesand networks connected in the IoT environment. In recent years, false DataInjection Attacks (fDIAs) have gained considerable interest in the IoT *** compromise the devices connected to the networkand inject the data. Such attacks on the IoT environment can result in a considerableloss and interrupt normal activities among the IoT network *** fDI attacks have been effectively overcome so far by conventional threatdetection techniques. The current research article develops a Hybrid DeepLearning to Combat Sophisticated false Data Injection Attacks detection(HDL-fDIAD) for the IoT environment. The presented HDL-fDIAD modelmajorly recognizes the presence of fDI attacks in the IoT *** HDL-fDIAD model exploits the Equilibrium Optimizer-based featureSelection (EO-fS) technique to select the optimal subset of the ***, the Long Short Term Memory with Recurrent Neural Network(LSTM-RNN) model is also utilized for the purpose of classification. At last,the Bayesian Optimization (BO) algorithm is employed as a hyperparameteroptimizer in this study. To validate the enhanced performance of the HDLfDIADmodel, a wide range of simulations was conducted, and the resultswere investigated in detail. A comparative study was conducted between theproposed model and the existing models. The outcomes revealed that theproposed HDL-fDIAD model is superior to other models.

关键词： false data injection attacks hyperparameter optimizer deep learning feature selection IoT security

Secondary neurogenesis and telencephalic organization in zebrafish and mice: a brief review

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Integrative Zoology 2009年第1期4卷 123-133页

作者： Mario f.WULLIMANN Department of Biology II Ludwig-Maximilians-UniversityMunich-MartinsriedGermany

Most zebrafish neurodevelopmental studies have focused on the embryo,which is characterized by primary neurogenesis of mostly transient *** neurogenesis becomes dominant in the hatching larva,when major brain parts are established and begin to *** developmental period allows for a comparative analysis of zebrafish brain organization with amniotes at equivalent stages of *** a particular time window,the early forebrains of mice(Embyronic stage[E]12.5/13.5 days[d])and zebrafish(3 d)reveal highly comparable expression patterns of genes involved in neurogenesis,for example proneural and other transcription factors(Neurogenin1,NeuroD,Mash1/Zash1a and Pax6).further topological correspondences are seen in the expression of LIM and homeobox genes,such as Lhx6/7,Tbr2 and *** this analysis is extended to gamma-aminobutyric acid/glutamic acid decarboxylase(GABA/GAD)cell patterns during this critical time window,an astonishing degree of similarity between the two species is again seen,for example regarding the presence of GABA/GAD cells in the subpallium,with the pallium only starting to be invaded by such cells from the ***,the expression of proneural and other genes correlates with GABA cell patterns(***1/Zash1a gene expression in GABA-positive and Neurogenin1/NeuroD in GABA-negative telencephalic regions)in mice and *** from additional vertebrates,such as Xenopus,are also highly consistent with this ***,the vertebrate forebrain appears to undergo a phylotypic stage of secondary neurogenesis,characterized by regionally separated GABAergic(inhibitory)versus glutamatergic(excitatory)cell production sites,which are obscured later in development by tangential *** period is highly advantageous for molecular neuroanatomical cross-species comparisons.

关键词： basal ganglia cortex subpallium tangential migration gamma-aminobutyric acid GABA.

function of seminal vesicles and their role on male fertility

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Asian Journal of Andrology 2001年第4期3卷 251-258页

作者： Gustavo f.Gonzales Department of Physiological Sciences Faculty of Sciences and Philosophy and Instituto de Invertigaciones de la Altura Universidad Peruana Cayetano Heredia Lima Peru

The present review has been designed to update the recent developments on the function of seminal vesicles andtheir role on male fertility. It is indicated that the true corrected fructose level is a simple method for the assessment ofthe seminal vesicular function. Measurement of seminal fructose used universally as a marker of the seminal vesiclefunction is not an appropriate approach due to its inverse relationship with the sperm count. The true corrected fructosedefined as [log. motile sperm concentration] multiplied by [seminal fructose concentration] has been shown to be abetter marker of the seminal vesicle function. Seminal vesicular secretion is important for semen coagulation, sperm motility, and stability of sperm chromatinand suppression of the immune activity in the female reproductive tract. In conclusion, the function of seminal vesicle is important for fertility. Parameters as sperm motility, sperm chro-matin stability, and immuno-protection may be changed in case of its hypofunction. (Asian J Androl 2001 Dec; 3:251 -258)

关键词： seminal vesicles male fertility male infertility true corrected fructose